They don't, actually. The article on wizarding currency says this:
The wizarding currency in the United States of America consists of the Dragot[1] and Sprink.[5]
The wizarding currency of France is Bezant.[6]
Oh thx
No. Some guy brought a giant hubcap sized coin in GoF.
I always assumed that that was a galleon, and he was exaggerating a little bit about the size.
What do you think?